Page 33 - PlayFacto_B11
P. 33
Counting in two ways
Find the number of visible faces in two different ways without counting
them.
Materials: Transparent case, Building blocks
Method 1 Take out the number of hidden faces
Imagine that
all the building blocks
are spread out. Then, take
the number of faces
that are stacked
together.
① Imagine all of seven building blocks are spread out to find the total
number of faces.
7^6=42 (faces)
② Find the number of hidden faces when building blocks are stacked
together.
stacked faces: 6 faces
hidden faces: 6^2=12 (faces)
③ Take the number of hidden faces ② from the total number of faces.
42-12=30 (faces)
30 Workbook B-11
Find the number of visible faces in two different ways without counting
them.
Materials: Transparent case, Building blocks
Method 1 Take out the number of hidden faces
Imagine that
all the building blocks
are spread out. Then, take
the number of faces
that are stacked
together.
① Imagine all of seven building blocks are spread out to find the total
number of faces.
7^6=42 (faces)
② Find the number of hidden faces when building blocks are stacked
together.
stacked faces: 6 faces
hidden faces: 6^2=12 (faces)
③ Take the number of hidden faces ② from the total number of faces.
42-12=30 (faces)
30 Workbook B-11
